Processing the Output of a Loop

Finally, you can either pipe or redirect the output of a loop within your shell script. You do this by adding the processing command to the end of the done command:

 for file in /home/rich/*
  do
    if [ -d "$file" ]
    then
       echo "$file is a directory"
    elif
       echo "$file is a file"
    fi
 done > output.txt

Instead of displaying the results on the monitor, the shell redirects the results of the for command to the file output.txt.

Consider the following example of redirecting the output of a for command to a file:

 $ cat test23
 #!/bin/bash
 # redirecting the for output to a file
 for (( a = 1; a < 10; a++ ))
 do
    echo "The number is $a"
 done > test23.txt
 echo "The command is finished."
 $ ./test23
 The command is finished.
 $ cat test23.txt
 The number is 1
 The number is 2
 The number is 3
 The number is 4
 The number is 5
 The number is 6
 The number is 7
 The number is...